Portable pump



FIG. 1 is a perspective view of my design for a portable pump;

FIG. 2 is a right side elevational view thereof;

FIG. 3 is a left side elevational view thereof;

FIG. 4 is a top view thereof;

FIG. 5 is a bottom view thereof;

FIG. 6 is a front elevational view thereof; and

FIG. 7 is a rear elevational view thereof. 

The ornamental design for a portable pump, as shown. 